import numpy as np
import math

def get_angel(x,y):
    Lx=np.sqrt(x.dot(x))
    Ly=np.sqrt(y.dot(y))
    cos_angle=x.dot(y)/(Lx*Ly)
    angle = np.arccos(cos_angle)*360/2/np.pi
    if np.cross(x,y) >= 0:
        angle = 360 - angle
    return angle

# 角度转弧度
def angle2pi(angle):
    return angle/180*math.pi